1. FIELD OF THE INVENTION
The present invention relates to a cacao butter substitute. More particularly, the present invention relates to a cacao butter substitute, especially a temper-type cacao butter substitute, wherein the saturated fatty acid radicals comprise substantially palmitic acid radical, stearic acid radical and arachidic acid radical; the unsaturated fatty acid radicals comprise substantially oleic acid radical and linoleic acid radical; and the proportions of respective triglycerides are critically limited.
2. DESCRIPTION OF THE PRIOR ART
Investigations and development of cacao butter substitutes are promoted by the insufficient supply of cacao butter due to an increase in the demand for chocolate. Cacao butter, which has been used advantageously as a butter ingredient of chocolate, has a characteristic physical property that, unlike other ordinary natural or processed oils or fats, it melts quite rapidly at a temperature near human body temperature, although it is solid at and below ambient temperature. This specific melting property of cacao butter is attributable to the fact that the triglycerides that constitute the cacao butter comprise substantially .beta.-unsaturated-.alpha., .alpha.'-disaturated triglycerides and the triglyceride composition as a whole is very simple.
An indispensable requirement of an acceptable cacao butter substitute is that at least its physical properties, particularly its melting property, must be substantially equivalent to those of cacao butter. The general fundamental ideas for imparting physical properties, equivalent to those of cacao butter, to a cacao butter substitute can be divided roughly into two ideas from the viewpoint of the triglyceride composition of the cacao butter substitute. One idea is that the triglyceride composition of the cacao butter substitute is made as close as possible to that of natural cacao butter. If the triglyceride composition of the cacao butter substitute is similar to that of natural cacao butter, the physical properties of the former are like those of the latter as a matter of course. The other idea is that the triglyceride composition of the cacao butter substitute is not necessarily made like that of natural cacao butter, but rather, only the physical properties, particularly the melting property, of the substitute are made equivalent to those of cacao butter. This is possible because substantially the same physical properties can be obtained even though the triglyceride compositions are different. In the classification of cacao butter substitutes based on triglyceride compositions, the former will be referred to hereinafter as "cacao butter-type cacao butter substitute" and the latter will be referred to as "non-cacao butter-type cacao butter substitute". Further, cacao butter substitutes are generally classified into "temper-type cacao butter substitutes" and "non-temper type-cacao butter substitutes", based on the differences in the steps of using same in preparing chocolate. The difference between them resides in whether or not it is necessary to use a tempering step (temper type) or it is unnecessary to use a tempering step (non-temper type) in the chocolate preparation process. Generally, it is considered that cacao butter-type cacao butter substitutes correspond to the temper type and non-cacao butter-type cacao butter substitutes correspond to the non-temper type.
Cacao butter-type cacao butter substitutes are prepared by fractionating natural oils and fats to obtain .beta.-unsaturated-.alpha., .alpha.'-disaturated triglycerides (hereinafter referred to as SUS). As a generally useful fractionation method, there may be mentioned solvent fractionation. As starting oils and fats to be subjected to the factionation, those containing a large amount of SUS triglyceride components are desirable.
One of the typical processes for preparing non-cacao butter type cacao butter substitutes comprises hydrogenating a starting oil to form a large amount of triglyceride components having a melting property like that of SUS-type triglycerides and then fractionating the same.
As is readily inferable from the triglyceride composition thereof, the melting property and the crystallizing property of a non-cacao butter-type cacao butter substitute change significantly if it is mixed with cacao butter, while such properties of cacao butter-type cacao butter substitute are not significantly changed by such mixing. Therefore, the mixing weight ratio of non-cacao butter-type cacao butter substitutes to cacao butter is naturally limited. The flavor and taste of cacao butter are very important for chocolate and, therefore, cacao butter-type cacao butter substitutes having a higher compatibility with cacao butter are far more desirable for the preparation of high quality chocolate. In the preparation of chocolate from cacao butter-type cacao butter substitute used together with cacao butter, a tempering step is inevitable. In this tempering step, a chocolate dough is cooled while it is undergoing kneading under proper conditions to form desired, stable crystal nuclei of oil and fat uniformly in the dough. After the subsequent molding and cooling tunnel steps, chocolate plates having uniform crystals therein and a smooth surface are obtained. By forming the uniform crystalline structure in the solid, the phenomenon of fat blooms, which is frequently observed during storage of chocolate, can be prevented. If the tempering step is omitted or if tempering is incomplete in this system, fat blooms are caused whereby the commercial value of the chocolate is lost.
When a non-temper type cacao butter substitute is used, the phenomenon of fat blooms is not so serious even if the tempering step (which is necessary when a temper type cacao butter substitute is used) is omitted. A reason therefor is considered to be that the triglyceride compositions of general non-temper type cacao butter substitutes are far more complicated than those of temper-type cacao butter substitutes or cacao butter and, in addition, the triglyceride crystals of the non-temper type cacao butter substitutes resulting after solidification by cooling are metastable and a very long period of time is required to transform them into the most stable crystals, namely, the transition is not effected during practical shelf life so that significant amounts of large crystals of oil and fat are not formed.
As the temper-type cacao butter substitutes of desirable triglyceride compositions, there may be mentioned those having triglyceride compositions very close to those of cacao butter. For example, in the specification of Japanese Pat. Laid-Open No. 9507/1974, it is disclosed that a preferred cacao butter substitute has a triglyceride composition wherein the sum of .beta.-oleopalmitostearotriglyceride (abbreviated as POSt) and .beta.-oleodistearotriglyceride (abbreviated as StOSt) which are the main ingredients of the triglyceride composition, is at least 85% based on the total triglycerides. The cacao butter substitutes in which the sum of POSt and StOSt is at least 85%, based on the total triglycerides, are highly compatible with cacao butter because the triglyceride compositions of the former are very close to that of the latter. However, it is to be noted that even if mixtures of those cacao butter substitutes and cacao butter are used, it is not always possible to prepare chocolate possessing satisfactory properties with respect to fat bloom resistance. This fact has been revealed by experiments wherein chocolates were prepared from cacao butter and cacao butter substitutes of known triglyceride compositions and then the chocolates were subjected to fat bloom resistance tests. In this connection, it is to be noted that chocolates prepared from only cacao butter do not have a high fat bloom resistance. Namely, since cacao butter is mainly comprised of .alpha.,.alpha.'-disaturated-.beta.-unsaturated symmetric triglycerides, its crystal transition proceeds far more rapidly in comparison with other oils and fats but, on the other hand, a considerable period of time is required for the transition into stable crystals in a sufficient amount, whereby fat blooms are liable to be formed. Accordingly, if the triglyceride composition of a cacao butter substitute is made close to that of cacao butter, the above properties of the cacao butter will be observed also in the cacao butter substitute. The fact that a cacao butter substitute having a triglyceride composition very close to that of natural cacao butter has a low fat bloom resistance is considered to be not due to poor compatibility with cacao butter, but rather, it is due to other reasons as described above. Another reason is that owing to the very simple triglyceride composition, the crystals grow into larger crystals which move out to the chocolate surface. The fat blooms reduce greatly the commercial value of chocolate. The fat blooms are apt to be formed particularly under storage conditions which involve large temperature changes. It is no exaggeration to say that the shelf life of chocolate in countries where there are large seasonal temperature changes, like in Japan, depends substantially on the fat bloom resistance of the chocolate.
Further, the known cacao butter substitutes having triglyceride compositions very close to those of cacao butter also have other properties of natural cacao butter which will be described below.
Cacao butter exhibits a specific melting property at its melting point of 34.degree. C., since it comprises mainly disaturated-unsaturated symmetric triglycerides (wherein the saturated acids are stearic acid and palmitic acid). However, generally in low temperature seasons in which chocolates are demanded in a larger amount, the specific melting property of cacao butter rather produces a feeling of a poor melting property in the mouth. For example, in most low-temperature districts of Japan such as Tohoku, Hokkaido, Hokuriku, ChubuSangaku and San'in Districts, chocolates comprising cacao butter produce a feeling of a poor melting property in the mouth during winter. The same phenomena will occur in the northern part of Europe and America, especially during the winter.
The first object of the present invention is to provide a temper-type cacao butter substitute possessing excellent physical properties, such as melting property in the mouth, which is free of the above-described defects of known cacao butter-type cacao butter substitutes and which has a high compatibility with cacao butter and remarkably improves the fat bloom resistance of chocolate made from a mixture of cacao butter and the cacao butter substitute according to the invention.
The second object of the present invention is to provide a temper-type cacao butter substitute having the properties desired in the preparation of chocolate such as a quick solidifying property and a releasing property.